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Search for "radical mediator" in Full Text gives 8 result(s) in Beilstein Journal of Organic Chemistry.
Free-radical cyclization approach to polyheterocycles containing pyrrole and pyridine rings
Beilstein J. Org. Chem. 2021, 17, 1490–1498, doi:10.3762/bjoc.17.105
- compounds are more expensive and less accessible than bromo-substituted analogs, we tried to accomplish the cyclization of pyridinium salt 1a using another radical mediator, tris(trimethylsilyl)silane (TTMSS) [31][32], which, moreover, is much less toxic than tributylstannane. Fortunately, free-radical
A review of asymmetric synthetic organic electrochemistry and electrocatalysis: concepts, applications, recent developments and future directions
Beilstein J. Org. Chem. 2019, 15, 2710–2746, doi:10.3762/bjoc.15.264
- lactonization of diols 51. However, in this method instead of a chiral base, they used 1-azaspiro[5.5]undecane N-oxyl 52 as a radical mediator for modifying the electrodes which resulted in optically active lactones 53 with enantiopurity of up to 99% (conditions B, Scheme 20) [52]. Chiral medium In this section
- -alcohols 63 via electrochemical oxidation in an undivided cell under constant current [61]. This time, they used catalytic amount of a different chiral N-oxyl radical mediator 64 (Scheme 25). The authors proposed that in the biphasic CH2Cl2/water medium, [Br+] is initially generated from [Br−] by
- supporting electrolyte. Asymmetric anodic oxidation of enol acetates using chiral supporting electrolytes. Kinetic resolution of primary amines using a chiral N-oxyl radical mediator
Vicinal difunctionalization of alkenes by four-component radical cascade reaction of xanthogenates, alkenes, CO, and sulfonyl oxime ethers
Beilstein J. Org. Chem. 2019, 15, 1822–1828, doi:10.3762/bjoc.15.176
- ) in C6H6 (16 mL) in the presence of hexabutylditin as a radical mediator, and DTBHN (di-tert-butyl hyponitrite) as a radical initiator was heated under CO (130 atm) at 45 °C for 16 h, the envisaged four-component coupling product, keto oxime 5a, was obtained in 43% yield, along with the three
Selective carboxylation of reactive benzylic C–H bonds by a hypervalent iodine(III)/inorganic bromide oxidation system
Beilstein J. Org. Chem. 2018, 14, 1087–1094, doi:10.3762/bjoc.14.94
- benzylic acetoxylation and benzoyloxylation of alkylbenzenes, where an in situ-generated sulfonamidyl radical is the essential radical mediator that effectively abstracts the benzylic hydrogen [49]. More recently, Maruoka et al. succeeded in the photolytic benzylic C–H bond oxygenation of alkylbenzenes
Metal and metal-free photocatalysts: mechanistic approach and application as photoinitiators of photopolymerization
Beilstein J. Org. Chem. 2014, 10, 863–876, doi:10.3762/bjoc.10.83
- through a subsequent Ph•/R3SiH hydrogen abstraction and R3Si•/PIC•+ interaction, respectively (the eA serves both as an electron donor and a radical mediator source) [45][46][47][48][49][50][51][52]. The Ph2I+/R3Si• interaction increases the yields in both phenyl radicals and silylium species [45][46][47
One-pot synthesis of cyanohydrin derivatives from alkyl bromides via incorporation of two one-carbon components by consecutive radical/ionic reactions
Beilstein J. Org. Chem. 2014, 10, 150–154, doi:10.3762/bjoc.10.12
- hydride [10][11][12][13] but also as the reagent for aldehyde reduction. Later on we found that borohydride reagents can also serve as radical mediator delivering hydrogen to the radical centre [14], thus we developed a hydroxymethylation method using Bu4NBH4 and a radical initiator [15][16][17]. Recent
- ). During the course of our study on borohydride-mediated radical hydroxymethylation of alkyl halides with CO, we found that cyanohydrin was obtained as a byproduct when Bu4NBH3CN was used as a radical mediator [15], which led us to investigate the one-pot synthesis of cyanohydrins based on radical
Flow Giese reaction using cyanoborohydride as a radical mediator
Beilstein J. Org. Chem. 2013, 9, 1791–1796, doi:10.3762/bjoc.9.208
- precursors, ethyl acrylate as a radical trap, and sodium cyanoborohydride as a radical mediator, were examined in a continuous flow system. With the use of an automated flow microreactor, flow reaction conditions for the Giese reaction were quickly optimized, and it was found that a reaction temperature of
- reductive radical addition reaction, better known as the Giese reaction, was historically carried out most by using tributyltin hydride as the radical mediator [8][9]. Recently borane derivatives such as borohydride reagents [10][11][12][13] or NHC-boranes [14][15][16][17][18] can be used in simple radical
- Scheme 2, higher reaction temperatures tended to result in the formation of increased amounts of octane (2a). Under the same reaction conditions, the radical mediator Bu4NBH3CN gave similar results, whereas the reaction with Bu4NBH4 was found not to be suitable, since the competing reduction leading to
Radical carbonylations using a continuous microflow system
Beilstein J. Org. Chem. 2009, 5, No. 34, doi:10.3762/bjoc.5.34
- pressurized carbon monoxide gas. Good to excellent yields of carbonylated products were obtained via radical formylation, carbonylative cyclization and three-component coupling reactions, using tributyltin hydride or TTMSS as a radical mediator. Keywords: continuous flow system; microreactor; radical
- carbonylation; radical mediator; V-65; Introduction Placing a reaction mixture fluid inside a microstructured channel network helps gain a high surface area to volume ratio that in turn ensures rapid heat and mass transfer [1][2][3]. Precise control of reaction temperature and residence time, excellent mixing
- in a controlled manner into the system and was mixed with the toluene solution containing a radical mediator, a radical initiator and a substrate in a T-shaped micromixer (stainless steel, internal diameter: 1000 μm). This biphasic (gas-liquid) mixture was then guided through a stainless steel
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